OK, your motor has an ADI ignition with 4 coils, right?
You should set the timing pointer to point correctly. To do this remove spark plugs and turn the motor until #1 cylinder is top dead center. A screwdriver can do this well enough. If you have a dial indicator, this is the time to use it. If not measure thru spark plug hole to top of piston. Add .464 inches to your measurement and turn flywheel until that measurement is achieved, thru the spark plug hole. The timing pointer should point to .464 on the timing decal. If not adjust it.
Remove the bottom 3 spark plugs, install them into their wires and ground them to the block. Put timing light on #1 spark plug (still installed on motor), and set throttle until carb is just about to open. Crank motor and read timing light. Set the middle adjustment screw on the throttle arm (near pivot) to achieve correct timing. Don't move throttle cable.
Set throttle to full and check timing. I would recommend you set max spark advance to 23* BTDC, rather than the 27* that was the original spec, as fuel is lower quality today.
